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Preout voltage vs amplifier input sensitivity?
#409577 01/18/15 07:03 PM
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I have an AVR capable of max preout voltage of 6v rms. Nominal is stated as 1v rms. It will be connected to 3 external amplifier channels with an input sensitivity of 311mv for max output. They will be used for the left/center/right speakers. The AVR will handle the rest of the channels in the surround system.

Is the great difference between ouput voltage vs input sensitivity going to cause volume/trim issues between the onboard vs external powered speakers? I dont want to run the L/C/R preouts at -10 to match the onboard amplification.

Am I screwed up at how I'm thinking of this? confused

Re: Preout voltage vs amplifier input sensitivity?
AAAA #409579 01/18/15 07:27 PM
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I found This to be easy to understand for a simple explanation. I read the article back when I was buying my first home amp. Car amps have variable input gain so I had to study up a bit.

Last edited by Socketman; 01/18/15 07:28 PM.

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Re: Preout voltage vs amplifier input sensitivity?
AAAA #409581 01/18/15 07:59 PM
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Thanks for the link!

Ok, I see the formula used equates to a voltage gain of 35.49 for the external amps. Seems really high. The manual states a max dc offset of 15mv. Whatever that means.

148w into 8 ohms. 285 into 4 ohms. From .311v input. Crazy.


According to the article this setup might be on the verge of too much of a good thing. I may be approaching my AVR preamp noise floor to make the external amp work out. How does anyone elses setup compare?

Last edited by Serenity_Now; 01/18/15 08:03 PM.
Re: Preout voltage vs amplifier input sensitivity?
AAAA #409583 01/18/15 08:19 PM
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Yes that is quite high and may cause the preamp to introduce noise into the signal, especially with very sensitive speakers.
Another good read.






Last edited by Socketman; 01/18/15 08:21 PM.

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Re: Preout voltage vs amplifier input sensitivity?
AAAA #409592 01/18/15 11:20 PM
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Ok, I'm not so concerned now after the 2nd article. Seems the nominal 1V output is perfectly fine for the input sensitivity. I just got hung up on the 6v max figure. That must be with the trim level at +10 or so. In any case, I wont know until I try.

Thanks for the info. smile

Re: Preout voltage vs amplifier input sensitivity?
AAAA #409604 01/19/15 03:24 AM
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Originally Posted By: Serenity_Now
... In any case, I wont know until I try.

Thanks for the info. smile

Hey, at least you know you don't need to turn it up to 11 to blow the roof off. smile


Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!
Re: Preout voltage vs amplifier input sensitivity?
AAAA #409617 01/19/15 03:26 PM
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Let us know how it goes. Hopefully they will maintain an equal volume level as things get turned up.


DOG is GOD spelled backwards.
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M80 V3 MY GLOSS Cherry

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